Spectrographic analysis was included on the video of Miles O'Brien's supposed death on the space station above T'Lani Prime in 2370. It revealed that the liquid O'Brien was drinking late in the afternoon was coffee. Keiko O'Brien used this fact, combined with her intimate knowledge of her husband, to conclusively declare that the video had been forged, because, she averred, Miles never drank coffee that late in the day. (DS9: "Armageddon Game")
The exact relationship between a spectroscopic analysis and a specrographic one is unknown, but it seems likely that they're related.